Periodic flooding of bodies of water has caused serious destruction and loss of life and property. In areas where flooding recurs, dams and levees have been built to contain rising waters. Sometimes these are sufficient, but more often s they are not and the water rises above the levees or is too powerful to be contained and breaks through them.
There have been many patents for portable dams developed for use in and alongside river beds and other waterways, but little has been done to devise portable means to stem the rise of flood waters other than the use of sandbags. Some inventors have utilized water as the ballast instead of sand.
Serota, in U.S. Pat. No. 3,213,628 teaches the use of plastic containers in the shape of a rectangular solid which can be filled with water and lashed together to form a wall or barrier. The containers can be stacked to form barriers of different heights, and additional units can be placed along the back side for added strength. The containers can be anchored to the ground to prevent movement. They are filled with water using a pump and are easily emptied when no longer needed. When empty, the containers are stored flat. The device of Serota is best used in a gorge or similar passageway.
Jackson, III, (U.S. Pat. No. 4,692,060) teaches an elongated water filled tube with side panels in the shape of an equilateral triangle. The tubes are surrounded by wooden frames fastened through loops in the sides of the tubes. The flames are used for support and to help in maintaining the triangular shape of the tubes when filled. The supported units can be placed end to end to form a wall of any desired length. The units can be stacked to double the height of the wall. The tubes and frames can easily be transported to a flood site and assembled. The tubes are filled by the use of a water pump. A similar device was developed by Coffey (U.S. Pat. No. 4,921,373), but he emphasizes an A-frame structure which can be made from highway or construction barriers. A flexible tube with triangular cross-section is supported by the frame and filled with water. The units can be placed end to end to extend the wall as needed. Velcro strips on the ends of the tubes facilitate fastening the units together. No stacking or backup row is noted.
Another long tubular container (can be 100 feet long) with triangular cross-section was developed by Hendrix (U.S. Pat. No. 5,040,919). The device of Hendrix is not in the form of an equilateral triangle, but one having sides of three different lengths. The longest side of the triangle faces the oncoming water, the side of median length forms the base and the shortest side is the back support. A skirt is attached to the container along the lower front edge to form a seal with the ground to prevent the rising waters from flowing under the unit. This device uses no outside support, but is very heavy when filled with water. Additional units can be placed end to end to provide a long wall. These units can not be stacked.
Another approach to the portable module as a flood barrier was taken by Taylor in U.S. Pat. No. 4,981,392. Taylor's module consists of two cylindrical chambers to be filled with water. The two cylinders are connected by a rectangular webbing proportioned to facilitate stacking the modules to form a barrier wall. The modules can be made in varying lengths. They can be placed side by side and/or stacked. A staggered stacking pattern can produce a barrier of considerable height and thickness. End to end placement results in a wall of any desired length. There is no mention of a ground seal or any means to prevent the flood water from passing beneath the modules.
All of the aforementioned devices may be effective in varying degrees in the path of rising water if the water is not too high, is not coming in rapidly and is not moving with great force. There is still a need for a strong, portable and easily constructed barrier for use against flood waters carrying considerable force so there is resistance to lateral movement as the waters rise and forces increase. There is also a need for such a unit to be sealed to the uneven ground so that swirling waters cannot undercut the ground support and cause the barrier to slide or shift position. A need exists for a continuous barrier of considerable weight and stability which can be further heightened quickly and easily without requiring additional weight or ballast. Such a barrier should be usable with a variety of ballast materials to accommodate materials available at the site or those most easily brought there.